1. Field of the Invention
The present invention relates to an optical disk apparatus having a plurality of heads (multi-heads) which can move independently in the radial direction of an optical disk.
2. Description of the Related Art
As a conventional optical disk apparatus of this type, there has been proposed an optical disk apparatus having a plurality of heads which can move independently in the radial direction of an optical disk as disclosed in Japanese Unexamined Patent Publication No. 3-260918 or No. 4-61050. With this configuration, since each of the plurality of heads can access a different track on the optical disk, both read and write operations, a plurality of write operations, and a plurality of read operations can be performed for one optical disk at the same time.
Methods for performing read and write operations while an optical disk is rotating include a constant angular velocity (CAV) method and a constant linear velocity (CLV) method. The above conventional optical disk apparatus handles a CAV-method disk. Since the linear velocity of a disk against each head differs unless the plurality of heads are disposed on the same track in the CLV method, signals read by the heads, which do not access at a constant linear velocity, have been compressed or expanded in the time domain. Therefore, the multi-head method cannot be applied to a CLV-method disk.